JPH10104585A - Cooling device of liquid crystal projection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device capable of cooling three liquid crystal modules to a same degree. SOLUTION: This cooling device for a liquid crystal projection is provided with an air duct 18 communicating with three liquid crystal modules 7, 9, 11 on an outside surface of the liquid crystal projection housing 1, and is also provided with a liquid crystal module cooling fan 15 on the other outside surface of the housing 1 facing the former outside surface, and by driving this liquid crystal module cooling fan 15, the fan 15 blows the air taken into the housing 1 to the air duct 18 through one or two of the three liquid crystal modules and further returns the air in the air duct 18 into the housing 1, ventilating the remaining two or one of the liquid crystal modules for releasing out of the housing 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projection cooling device.

[0002]

2. Description of the Related Art In optical components such as a liquid crystal panel and an incident side polarizing plate in a liquid crystal module incorporated in a liquid crystal projection, a part of light emitted from a projection lamp changes into heat and becomes high temperature. In order to maintain the above characteristics and prevent aging, it is necessary to cool down to keep the temperature below the specified allowable temperature.

In particular, in a three-panel type liquid crystal projection using three sets of liquid crystal modules, since the heat generation amounts of the respective liquid crystal modules are different, the temperature of the liquid crystal module having the largest heat generation is lowered and the three liquid crystal modules are set to the same degree. A cooling device that efficiently cools to a temperature is desired, and the structure is preferably a small structure that does not adhere dust to the liquid crystal panel and is small and easy to manufacture. Such a cooling device is generally performed by an air cooling system using a cooling fan. As the cooling device of the air cooling system, there is the following conventional technology.

(1) Sequential ventilation system As shown in FIG.
Then, air is sequentially passed through each of the three liquid crystal modules 31, 32, and 33, and the warmed air is discharged from the third liquid crystal module 33 to the outside. When a cooling system is formed by a closed circuit for the purpose of dust prevention, a closed circuit is formed by connecting a cooling fan outside the optical system housing by using a duct bypassing the optical system housing.

(2) Distribution method by ventilation guider As shown in FIG. 13, three liquid crystal modules 31 are provided depending on the shape of the guider and the position of the cooling fan 30 for cooling the liquid crystal module.
The air flow is distributed in accordance with the heat generation amounts of 33 to 33, and the air is passed in parallel. When a cooling system is formed by a closed circuit for the purpose of dust prevention, a closed circuit is formed by connecting a cooling fan outside the optical system housing by using a duct bypassing the optical system housing.

[0006]

The sequential ventilation system described above is
This is a cooling method in which the air flow obtained by the cooling fan is distributed to each liquid crystal module sequentially without distributing the air flow using a complicated shape guider.Therefore, three liquid crystal modules are structurally ducted. Since it may be simply connected, a simple structure can be obtained. However, in order to let air flow through the air passage with small gaps connecting the liquid crystal modules in series,
The cooling efficiency is low because the pressure loss in the air passage is high and the amount of air cannot be increased, and the surface temperature of the three liquid crystal modules rises from the cooling air temperature because the heat transfer coefficients in the liquid crystal modules are almost the same. Therefore, if there is a large difference between the calorific values of the respective liquid crystal modules in proportion to the calorific value, the liquid crystal modules cannot be cooled to the same temperature.

In the case where a cooling system with a closed circuit is formed by the sequential ventilation system for the purpose of dust protection, a cooling air inlet to the first liquid crystal module is connected to a cooling air outlet of the third liquid crystal module. It is necessary to connect the cooling fan to the cooling fan by using a duct that bypasses the optical system housing to form a closed circuit, so that the structure is small and the structure is not simple in manufacturing.

The latter distribution method using a guider is a method of distributing the air flow to three liquid crystal modules by a guider installed near a cooling fan, so that it can be designed to be relatively compact, and many liquid crystals are currently used. It is used as a cooling device for projection. However, since the air is distributed to the three directions at the entrance, the amount of air flowing through one liquid crystal module is small and the cooling efficiency is low. In addition, it is technically difficult to distribute the air flow according to the shape of the guider and the position of the cooling fan in accordance with the heat generated by the three liquid crystal modules. This is not an easy method because you need to repeat the error experiment.

In the case of forming a cooling system with a closed circuit for the purpose of dust prevention in this distribution system, the optical system housing extends from the cooling air intakes of all the liquid crystal modules to the cooling air outlets of all the liquid crystal modules. It is necessary to connect to the cooling fan by using a duct bypassing the above, and to form a closed circuit, so that the structure is small and the structure is not simple in manufacturing.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a cooling device excellent in cooling performance and manufacturability. Another object of the present invention is to provide a closed-circuit cooling device for dust prevention, which is excellent in manufacturability.

[0011]

According to a first aspect of the present invention, there is provided a liquid crystal projection cooling device for cooling three liquid crystal modules corresponding to three primary colors of light of a liquid crystal projection, wherein one of outer surfaces of a housing of the liquid crystal projection is provided. And an air duct communicating with the three liquid crystal modules in an air manner, and a cooling fan for the liquid crystal module provided on the other outer surface of the housing opposed to the one outer surface, and the cooling fan for the liquid crystal module is driven by the cooling fan. The air sucked into the housing by the cooling fan
One or two of the two liquid crystal modules to reach the air duct, and return the air entering the air duct to the inside of the housing again and pass the remaining two or one liquid crystal module to the outside of the housing. It is characterized in that it is released to

According to this structure, by driving the liquid crystal module cooling fan, the sucked cold air is first given to the liquid crystal module having the largest calorific value to be cooled, and thereafter,
Either distribute and pass through the remaining liquid crystal modules having a small calorific value, or first supply the sucked cold air to two liquid crystal modules having a small calorific value to cool both of the liquid crystal modules, and then the remaining calorific value It is sent to a liquid crystal module that has a lot of liquid and cooled. As a result, the cooling air is intensively sent to the liquid crystal module that generates a large amount of heat to cool the liquid crystal module, so that the three liquid crystal modules can be cooled to the same extent. In addition, it is possible to efficiently send an appropriate amount of air by reducing the pressure loss of the air passage to the three liquid crystal modules, and to efficiently cool each liquid crystal module.

According to a second aspect of the present invention, there is provided a liquid crystal projection cooling apparatus according to the first aspect, wherein a dustproof filter is provided on the liquid crystal module cooling fan side, and the liquid crystal module cooling fan is provided. The air passing through the dustproof filter is sucked into the housing by the driving of the device. According to this configuration, it is possible to supply clean air that does not contain dust through the dustproof filter, and does not stain the liquid crystal module. As a result, the liquid crystal module can be kept clean at all times, and a clear image can always be obtained.

According to a third aspect of the present invention, there is provided a liquid crystal projection cooling device for cooling three liquid crystal modules corresponding to three primary colors of liquid crystal projection light, wherein the three liquid crystal modules are provided on two outer surfaces of a housing of the liquid crystal projection. Providing the first and second air ducts leading to the first air duct, one or two of the three liquid crystal modules, the second air duct and the third liquid crystal module. Forming a closed circuit of air consisting of the remaining two or one path, and providing a cooling fan for a liquid crystal module in at least one of the two air ducts. Forming a flow of air in a closed circuit
One liquid crystal module is cooled.

According to this configuration, each video module is cooled by the air in the closed circuit without taking in any external air. As a result, there is no need to worry about soiling the image module with dust and the like contained in the external air, and a clear image can always be obtained.

A cooling device for a liquid crystal projection according to a fourth aspect of the present invention is the cooling device for a liquid crystal projection according to the third aspect, wherein a heat absorber is provided in at least one of the two air ducts. A radiator thermally coupled to a heat absorber is provided outside the air duct. According to this configuration, the air in the closed circuit is cooled by the heat absorber and the radiator thermally coupled to the heat absorber. As a result, the liquid crystal module can be cooled more efficiently.

A cooling device for a liquid crystal projection according to a fifth aspect of the present invention is the cooling device for a liquid crystal projection according to the third aspect, wherein a heat absorber is provided in at least one of the two air ducts. A radiator thermally connected to a heat sink is provided outside the air duct, and a Peltier element having a low-temperature end connected to the heat sink and a high-temperature end connected to the radiator. It is characterized by having been provided. According to this configuration, the heat radiation effect by the heat absorber and the radiator can be further enhanced by the Peltier element. As a result, the liquid crystal module can be cooled more efficiently.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram of a liquid crystal projection provided with a cooling device according to the present invention as viewed from above, and FIG. 2 is a schematic diagram of the same liquid crystal projection as viewed from the front. In these figures, reference numeral 1 denotes an optical system housing, and a cover 2 is integrally provided at a rear portion thereof, and a projection lamp 3 and a lamp cooling fan 4 are provided therein. .

The light emitted from the projection lamp 3 enters the housing 1, and firstly, only the red light is reflected by the first dichroic mirror 5 and sent to the reflection mirror 10. The red light reflected by the reflection mirror 10 is the third light for red.
After passing through the liquid crystal module 11 and the third dichroic mirror 12, the light is reflected by the fourth dichroic mirror 13 and sent to the projection lens 14.

The light that has passed through the first dichroic mirror 5 is separated into blue light and green light by a second dichroic mirror 6, and the blue light passes through a second liquid crystal module 9 and passes through a third liquid crystal module 9. The light is sequentially reflected by the fourth dichroic mirrors 12 and 13 and sent to the projection lens 14. On the other hand, the green light passes through the second dichroic mirror 6, passes through the first liquid crystal module 7, and is sent to the projection lens 14 via the reflection mirror 8 and the fourth dichroic mirror 13.

Each of the liquid crystal modules 7, 9 and 11 includes an incident-side polarizing plate 7a, 9a and 11a, and an outgoing-side polarizing plate 7, respectively.
b, 9b and 11b, and liquid crystal panels 7c, 9c and 11c located between these polarizers.
A cooling device is necessary because some of the input light energy is converted into heat by these optical components. The heat value of each liquid crystal module is determined by the characteristics of the projection lamp 3 and the characteristics of each dichroic mirror.

Reference numeral 15 denotes a cooling fan for the liquid crystal module disposed outside the bottom surface of the housing 1 so as to oppose the second liquid crystal module 9. As shown by the arrow in FIG. 2, the total amount of cooling air is
First, the liquid crystal is sent to the second liquid crystal module 9 which generates the largest amount of heat, and then is once taken out of the housing 1 and returned to the housing 1 again through the air duct 18 installed on the upper surface side of the housing 1. , Are supplied to the first and third liquid crystal modules 7 and 11 located on both sides of the second liquid crystal module 9 and finally discharged from the bottom side of the housing 1 to the outside of the housing 1. . The liquid crystal module cooling fan 15 and the dustproof filter 16 are provided on the holding frame 1 provided on the bottom of the housing 1.
7.

As described above, a large cooling effect can be obtained by first supplying the air sucked by the liquid crystal module cooling fan 15 to the second liquid crystal module 9 having the largest calorific value. The calorific value of the three liquid crystal modules as described above is generally proportional to the heat flow rate incident on the liquid crystal module. However, taking a certain product as an example, the incident heat flow rate is as shown in Table 1.

[0024]

[Table 1]

As is clear from Table 1, the ratio of the incident heat velocities of the liquid crystal modules can be said to be about 1: 2: 1. Here, the heat transfer coefficient on the liquid crystal module surface according to the related art and the present invention will be compared. K ₀ in a sequential ventilation system heat transfer coefficient on the panel surface when it sent the Zenkazeryou in one liquid crystal module using the same cooling fan, K ₁ in the distribution system, when the K ₂ in the manner of the present invention, the ventilation system, based on the total liquid crystal module, for passing sequentially total air volume, the heat transfer rate in each of the liquid crystal module are the same and are K _0. Next, in the distribution method, g, b, and r are supplied to each of the liquid crystal modules 7, 9 and 11.
If (g + b + r = 1), it is generally considered that the heat transfer coefficient is proportional to the 0.5th power of the wind speed, so that g ＾ 0.5 * K ₁ , b ＾ 0.
5 * the K ₁ and r ^ 0.5 * K _1.

In contrast, in the present invention, 0.5 ＾ 0.5.
* K ₂ , K ₂ and 0.5 ＾ 0.5 * K ₂ . Since the temperature rise of the liquid crystal module is proportional to the incident heat flow rate, the incident heat flow rate at each liquid crystal module is determined by Q, 2 from the results shown in Table 1.
Assuming Q and Q, the temperature rise values in each liquid crystal module are as shown in Table 2 below.

[0027]

[Table 2]

Referring to Table 2 above, when the system of the present invention and the sequential ventilation system are compared, it is clear that the sequential ventilation system has a longer air path and a larger ventilation resistance, so that the same cooling fan is used. Since the amount of air that can be taken is small and K ₀ <K ₂ ,
2Q / K ₀ <2Q / K ₂ , indicating that the ventilation system according to the present invention can lower the highest temperature rise value.

Next, when the method of the present invention is compared with the guider distribution method, the magnitude relationship between K ₁ and K ₂ is not absolutely determined, but b <1 from g + b + r = 1. Due to the influence, the present invention has a greater cooling effect for the highest temperature rise value. For example, in a comparative experiment on a certain product, as shown in Table 3, the ventilation system according to the present invention was superior in the second liquid crystal module 9.

[0030]

[Table 3]

FIG. 3 shows a second embodiment of the present invention. In this embodiment, a cooling fan 1 for cooling a liquid crystal module is provided.
5 is supplied first to the first and third liquid crystal modules 7 and 11, and then the air passing through these modules is sent to the second liquid crystal module 9 via the air duct 18, and finally To be released outside the housing 1. Also in this configuration, the same effect as in the first embodiment can be expected.

The cooling fan 15 for cooling the liquid crystal module in the first and second embodiments uses a propeller fan which is generally used. Since the propeller fan cannot obtain a large static pressure, it is necessary to design the ventilation opening of the liquid crystal module as wide as possible.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, a sirocco fan is used as a cooling fan for a liquid crystal module. In this embodiment, the air duct 18 is arranged on the bottom side of the housing 1, and the sirocco fan as the liquid crystal module cooling fan 15 a is provided in the air duct 18, while the dustproof filter is provided on the upper surface of the housing 1. 16 are arranged by a holding frame 17.
Accordingly, in this configuration, when the liquid crystal module cooling fan 15a is driven, the air sucked into the housing 1 through the dustproof filter 17 first passes through the second liquid crystal module 9 and once goes out of the housing 1. Later, air duct 1
8 again returns to the inside of the housing 1, this time passing through the first and third liquid crystal modules 7 and 11, and then
Released outside.

FIG. 5 shows a fourth embodiment of the present invention. In this embodiment, a dustproof filter 16 and an air duct 18 are provided at the same position with respect to the housing 1 as in the first embodiment. Instead of providing a liquid crystal module cooling fan on the dustproof filter 16 side, a connection duct 19 connecting the first and third liquid crystal modules 7 and 11 and the lamp cooling fan 4 on the bottom side of the housing 1. Is provided.

With this configuration, when the lamp cooling fan 4 is driven, the air sucked through the dustproof filter 16 first enters the housing 1 and passes through the second liquid crystal module 9, and then temporarily once. Go outside and air duct 1
8 again into the housing, this time passing through the first and third liquid crystal modules 7 and 11 to reach the outside of the housing 1 again,
Finally, the fan 4 for cooling the lamp is connected to the connecting duct 19.
Leads to.

FIG. 6 shows a fifth embodiment of the present invention. In this embodiment, air ducts 18 and 18a are provided on the upper surface and the bottom surface of the housing 1, respectively, and a liquid crystal module is provided in the lower air duct 18a. A cooling fan 15 is provided,
By driving the cooling fan 15 for the liquid crystal module, the fan 15, the air duct 18 of the second liquid crystal module 9, and the first
And third liquid crystal modules 7, 11 and air duct 1
8a form a closed circuit for the flow of air through it. In this case, the heat is radiated to the outside via the air ducts 18 and 18a, so that dust contained in the outside air can be prevented from adhering to the liquid crystal module.

FIG. 7 shows a sixth embodiment of the present invention. In this embodiment, while the fifth embodiment uses a propeller fan as a cooling fan for a liquid crystal module, a sirocco fan is used. 15a is used. FIG. 8 shows a seventh embodiment of the present invention. In this embodiment, a heat absorber 20 is provided inside the air duct 18 in addition to the configuration of the sixth embodiment shown in FIG. A radiator 21 thermally coupled to the heat sink 20 is provided outside the duct 18, and further, the radiator 21 is connected to the lamp cooling fan 4 on the upper surface of the housing 1 on the side where the radiator 21 is located. Cooling duct 22 is provided.

Therefore, according to this configuration, the sirocco fan 15a, the second liquid crystal module 9, the air duct 18, the first and third sirocco fans 15a are driven by the driving of the sirocco fan 15a.
A closed circuit of the flow of the air passing through the liquid crystal modules 7 and 11 and the air duct 18a is formed to cool each liquid crystal module, and the heat of the air flowing through the closed circuit is removed by the heat absorber 20 and the heat is removed. This heat sink 20
The heat is radiated to the outside by a radiator 21 which is thermally coupled to the radiator 21, and the radiator 21 is further cooled by wind of a lamp cooling fan 4 flowing through a cooling duct 22.

FIG. 9 shows an eighth embodiment of the present invention. In this embodiment, in addition to the configuration of the sixth embodiment shown in FIG. 7, an air duct 18a is provided on the air duct 18a side. A sirocco fan 23 coaxially driven with the sirocco fan 15a is provided outside, and an air duct 18 is provided.
a, heat absorbers 24 on both sides of the sirocco fan 15a,
24, and radiators 25, 25 thermally coupled to the heat absorbers 24, 24 on both sides of the sirocco fan 23 outside the air duct 18.

Therefore, according to this configuration, the sirocco fan 15a, the second liquid crystal module 9, the air duct 18, the first and third sirocco fans 15a are driven by the driving of the sirocco fan 15a.
A closed circuit of the flow of air passing through the liquid crystal modules 7, 11 and the air duct 18a is formed to cool each liquid crystal module, and the heat of the air flowing through the closed circuits is removed by the heat absorbers 24, 24. A radiator 25, 25 thermally coupled to the heat absorbers 24, 24
Then, the heat is radiated to the outside, and the radiators 25 are cooled by the wind flowing through the sirocco fan 23.

FIG. 10 shows a ninth embodiment of the present invention. In this embodiment, in addition to the seventh embodiment shown in FIG. A Peltier device 26 is provided in which the low-temperature end is thermally coupled to the heat sink 20 and the high-temperature end is thermally coupled to the radiator 21. Reference numeral 27 denotes a DC power supply for the Peltier element 26. With this configuration, the heat of the liquid crystal module can be more efficiently removed using the Peltier element 26. Of course, in this configuration, the heat of the Peltier element can be cooled by the lamp cooling fan 4. FIG. 11 shows the first embodiment of the present invention.
0 shows the embodiment of FIG.
In the embodiment, each of the heat sinks 24 and the radiators 25
Are provided with a Peltier element 28. Note that a common DC power supply 29 is provided for these Peltier elements 28, 28.

[0042]

According to the present invention, the cooling device for a liquid crystal projection according to the first aspect of the present invention is a cooling device for a liquid crystal projection corresponding to three primary colors of light.
In an apparatus for cooling one liquid crystal module, an air duct communicating with the three liquid crystal modules is provided on one outer surface of a liquid crystal projection housing, and a liquid crystal module cooling fan is provided on the other outer surface of the housing opposed to the one outer surface. By driving the liquid crystal module cooling fan, the air sucked into the housing by the liquid crystal module cooling fan is caused to reach the air duct through one or two of the three liquid crystal modules, and In this configuration, the air that has entered the duct is returned to the inside of the housing again, passes through the remaining two or one liquid crystal module, and is discharged outside the housing.

According to the present invention, by driving the liquid crystal module cooling fan, the sucked cold air is first given to the liquid crystal module having the largest calorific value to be cooled.
Either distribute and pass through the remaining liquid crystal modules having a small calorific value, or first supply the sucked cold air to two liquid crystal modules having a small calorific value to cool both of the liquid crystal modules, and then the remaining calorific value It is sent to a liquid crystal module that has a lot of liquid and cooled. Therefore, the cooling air is intensively sent to the liquid crystal module that generates a large amount of heat to cool the liquid crystal module, and the three liquid crystal modules can be cooled to the same extent. In addition, the pressure loss of the air passages in the three liquid crystal modules is reduced, so that an appropriate amount of air can be efficiently kept, and each liquid crystal module can be cooled efficiently.

According to a second aspect of the present invention, in the cooling device for a liquid crystal projection according to the first aspect of the present invention, a dustproof filter is provided on the liquid crystal module cooling fan side, and The configuration is such that the air that has passed through the dustproof filter is sucked into the housing by driving the fan.
According to the present invention, it is possible to supply clean air that does not include dust passing through the dustproof filter, and does not stain the liquid crystal module. Therefore, the liquid crystal module can always be kept clean, and a clear image can be always obtained.

According to a third aspect of the present invention, there is provided a liquid crystal projection cooling device for cooling three liquid crystal modules corresponding to three primary colors of light of a liquid crystal projection.
By providing first and second air ducts communicating with the three liquid crystal modules on two outer surfaces of the housing of the liquid crystal projection, one or two of the first air duct and the three liquid crystal modules are provided. , The remaining two or one of the second air duct and the third liquid crystal module.
Forming a closed circuit of air composed of two paths, and providing a cooling fan for a liquid crystal module in at least one of the two air ducts; Is formed to cool the three liquid crystal modules.

According to the present invention, each video module is cooled by the air in the closed circuit without taking in any external air. Therefore, a clear image can always be obtained without having to worry about soiling the image module with dust and the like contained in the external air.

According to a fourth aspect of the present invention, there is provided a cooling device for a liquid crystal projection according to the third aspect, wherein a heat absorber is provided in at least one of the two air ducts. In this configuration, a radiator thermally coupled to the heat absorber is provided outside the air duct. According to the present invention, the air in the closed circuit is cooled by the heat sink and the radiator thermally coupled to the heat sink. Therefore, the liquid crystal module can be cooled more efficiently.

The cooling device for a liquid crystal projection according to the invention of claim 5 is the cooling device for a liquid crystal projection according to claim 3, wherein a heat absorber is provided in at least one of the two air ducts. A radiator provided outside the air duct and thermally coupled to a heat sink, and a low-temperature end portion is thermally coupled to the heat sink and a high-temperature end portion is thermally coupled to the radiator, respectively. This is a configuration in which elements are provided. According to the present invention, the heat dissipation effect by the heat absorber and the radiator can be further enhanced by the Peltier element. Therefore, the liquid crystal module can be cooled more efficiently.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a liquid crystal projection including a cooling device according to a first embodiment of the present invention as viewed from above.

FIG. 2 is a schematic configuration diagram illustrating a liquid crystal projection including the cooling device according to the first embodiment.

FIG. 3 is a schematic configuration diagram showing a second embodiment of a liquid crystal projection cooling device of the present invention.

FIG. 4 is a schematic configuration diagram showing a third embodiment of a cooling device for liquid crystal projection according to the present invention.

FIG. 5 is a schematic configuration diagram showing a fourth embodiment of a liquid crystal projection cooling device of the present invention.

FIG. 6 is a schematic configuration diagram showing a fifth embodiment of the liquid crystal projection cooling device of the present invention.

FIG. 7 is a schematic structural view showing a sixth embodiment of the liquid crystal projection cooling device of the present invention.

FIG. 8 is a schematic configuration diagram showing a cooling device for liquid crystal projection according to a seventh embodiment of the present invention.

FIG. 9 is a schematic configuration diagram showing an eighth embodiment of a liquid crystal projection cooling device of the present invention.

FIG. 10 is a schematic configuration diagram showing a ninth embodiment of a cooling device for liquid crystal projection according to the present invention.

FIG. 11 is a schematic structural view showing a cooling device for a liquid crystal projection according to a tenth embodiment of the present invention.

FIG. 12 is a schematic configuration diagram showing an outline of a conventional cooling device of a sequential ventilation system.

FIG. 13 is a schematic configuration diagram showing an outline of a conventional cooling device of a distribution type using a ventilation guider.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 housing 3 projection lamp 4 lamp cooling fan 7 first liquid crystal module 9 second liquid crystal module 11 third liquid crystal module 15 liquid crystal module cooling fan 16 dustproof filter 18 air duct 20 heat sink 21 radiator

Claims (5)

[Claims] 1. An apparatus for cooling three liquid crystal modules corresponding to three primary colors of light of a liquid crystal projection, wherein an air duct communicating with the three liquid crystal modules is provided on one outer surface of a housing of the liquid crystal projection, and the one outer surface is provided with the air duct. A liquid crystal module cooling fan is provided on the other outer surface of the opposing housing, and the air sucked into the housing by the liquid crystal module cooling fan is driven by the driving of the liquid crystal module cooling fan. Through one or two to the air duct, and
A cooling device for a liquid crystal projection, wherein the air that has entered the air duct is returned into the housing again, passes through the remaining two or one liquid crystal module, and is discharged outside the housing. 2. The liquid crystal module cooling fan is provided with a dust filter on a side thereof, and the air passing through the dust filter is sucked into the casing by driving the liquid crystal module cooling fan. 2. The cooling device for liquid crystal projection according to 1. 3. A cooling device for cooling three liquid crystal modules corresponding to three primary colors of light of a liquid crystal projection, wherein first and second air ducts connected to the three liquid crystal modules are provided on two outer surfaces of a housing of the liquid crystal projection. From the first two air ducts, one or two of the three liquid crystal modules, the second air duct and the remaining two or one of the three liquid crystal modules. A liquid crystal module cooling fan is provided in at least one of the two air ducts, and the air flow is formed in the air closed circuit by driving the liquid crystal module cooling fan. Above 3
A cooling device for a liquid crystal projection, wherein two liquid crystal modules are cooled. 4. A heat sink is provided in at least one of the two air ducts, and a radiator thermally coupled to the heat sink is provided outside the air duct. Item 4. A cooling device for liquid crystal projection according to item 3. 5. A heat sink is provided in at least one of the two air ducts, and a radiator thermally connected to the heat sink is provided outside the air duct, and the heat sink has a low temperature. 4. The cooling device for a liquid crystal projection according to claim 3, further comprising a Peltier element having a side end thermally coupled to the high-temperature side end of the radiator.